Curved slab surfaces, systems, and methods

ABSTRACT

Systems and methods of thermoforming stone slabs are provided, such as by heating a stone slab while forming it to a mold. Curved stone slabs may be produced having low radii of curvature.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of and claims priority toU.S. application Ser. No. 15/714,827, filed on Sep. 25, 2017.

TECHNICAL FIELD

This document describes slabs having curved surfaces, and systems andprocesses for manufacturing slabs having curved surfaces.

BACKGROUND

Stone slabs are a commonly used building material. Granite, marble,soapstone, and other quarried stones are often selected for use ascountertops, tables, and floors. Stone slabs may be formed from acombination of materials that can provide improved aestheticcharacteristics, strength, and stain-resistant or heat resistantproperties.

The properties of stone make it a suitable candidate for otherapplications, including wall panels, shower and bath surrounds, tableand counter top bases, sinks, reception area installments, anddecorative installments. Quarried and processed stone slabs aretypically cut to a desired size and shape prior to installation. Unlikegranite and other quarried stone slabs, processed stone slabs aregenerally formed from a mix including particulate mineral material and abinder, which is then vibro-compacted and heated or otherwise cured toprovide a slab. Such molding methods for processed stone slabs typicallyresult in a rectangular slab with substantially flat major surfaces.

SUMMARY

Some embodiments described herein include curved slabs, and systems andprocesses for forming curved slabs, for use in living or working spaces(e.g., along a countertop, table, floor, wall, or the like). In someembodiments, the slabs are processed slabs formed from a combination ofmaterials, such as particulate mineral material and a binder (e.g., apolymer resin, cement, etc.). In some embodiments, a combination ofmaterials optionally includes quartz, one or more pigments, and one ormore resin binders.

Some exemplary systems and processes described herein may includeapplying conductive heat simultaneously to first and second majorsurfaces of a slab comprising particulate material, and forming the slabto a mold while applying the conductive heat to the first and secondmajor surfaces. A slab may be formed having a selected curvaturesuitable for a particular installation, with reduced processing timeand/or manual labor.

In one aspect, a method is provided herein for thermoforming a slab. Themethod includes applying conductive heat simultaneously to a first majorsurface and a second major surface of a slab comprising particulatematerial and forming the slab to a mold while applying the conductiveheat to the first and second major surfaces. The first major surface ofthe slab can be separated from the second major surface by a slabthickness. Optionally, the mold comprises a curved molding surface, andthe step of forming the slab to the mold comprises applying theconductive heat to the first and second major surfaces of the slab whileat least one of the major surfaces is urged toward the curved moldingsurface of the mold.

In some implementations, the method can optionally include one or moreof the following features. Applying heat can include heating a firstconductive pad positioned on the first major surface of the slab.Applying heat may further include heating a second conductive padpositioned on the second major surface of the slab. In someimplementations, the step of forming the slab can include forming acurve having a radius of curvature of less than 100 inches. In someimplementations, the step of forming the slab can include forming acurve having a radius of curvature of 18 inches or greater. In someimplementations, the step of forming the slab can include forming acurve having a radius of curvature of between 23 inches and 80 inches.The radius of curvature can be a minimum radius of curvature. The slabcan comprise a particulate material, one or more pigments, and one ormore resin binders. The particulate material can comprise predominantlyquartz. The slab can have a first major surface and a second majorsurface separated by a thickness, and the thickness can be between 0.001inches and 3 inches. In some implementations, the thickness of the slabcan be between 0.003 inches and 2 inches. Applying conductive heat caninclude applying heat at a slab moldable temperature, the slab at leastpartially malleable when heated to the slab moldable temperature. Insome implementations, applying conductive heat can include applyingconductive heat at a temperature between 50° C. to about 150° C. Theslab can comprise a binder material having a glass transitiontemperature (Tg). Applying conductive heat optionally can includeapplying heat at a temperature within 20° C. of the glass transitiontemperature (Tg).

In some implementations, the method can optionally further includesecuring the slab to the mold for a first period of time. In someimplementations, the method can optionally further include manufacturingthe slab by compacting, compressing, and at least partially curing theslab prior to applying conductive heat to the slab. In someimplementations, the method can optionally further include clamping theslab in a first curved configuration for a first period of time whileheat is simultaneously applied to the first and second major surfaces toform a first curve having a first radius of curvature; and clamping theslab in a second curved configuration for a second period of time whileheat is simultaneously applied to the first and second major surfaces toform a second curve having a second radius of curvature.

In another aspect, a method is provided herein for thermoforming a slab,including applying conductive heat simultaneously to a first majorsurface and a second major surface of a slab comprising particulatematerial, the first major surface separated from the second majorsurface by a slab thickness; and forming the slab to a mold whileapplying the conductive heat to the first and second major surfaces byheating a first conductive pad positioned on the first major surface ofthe slab and heating a second conductive pad positioned on the secondmajor surface of the slab; wherein the resulting slab includes a curvehaving a minimum radius of curvature between 18 inches and 100 inches.The slab can optionally comprise a particulate material, one or morepigments, and one or more resin binders, and applying conductive heatcomprises applying heat at a temperature within 20° C. of the glasstransition temperature (Tg) of the one or more resin binders.

In another aspect, a method is provided herein for thermoforming a slab,including forming the slab to a curved surface of a mold while applyingthe conductive heat to first and second major surfaces of the slab.

In another aspect, a processed slab having a curved shape is provided.The processed slab can comprise a first major surface separated from anopposing second major surface by a slab thickness; a mix of particulatemineral material; one or more pigments; and one or more resin binders,wherein both the first major surface and second major surface areconductively heated and are curved and parallel to one another.Optionally, at least one of the first major surface and second majorsurface of the processed slab has a radius of curvature of less than 100inches, less than 80 inches, less than 60 inches, or less than 30inches. The processed slab can be at least partially malleable.Optionally, the temperature of the processed slab is a slab moldabletemperature. The one or more binders can have a glass transitiontemperature (Tg) and the slab moldable temperature can optionally bewithin 20° C. of the glass transition temperature (Tg).

The slabs, systems and methods described herein can provide severaladvantages. First, thermoforming slabs by applying conductive heat tomultiple surfaces (e.g., top and bottom major surfaces) facilitatessubstantially consistent heating of the slab through the entirethickness of the slab. Conductive heat provides controlled and efficientheat transfer such that the slab may be heated to a temperature suitablefor molding based on characteristics of a polymer binder or othercomponents within the slab.

Second, various curved slabs, systems and methods described herein canprovide tighter curves (e.g., with a smaller radius of curvature) inless time and/or with less manual labor/intervention. For example,application of conductive heat sources simultaneously to top and bottommajor surfaces can improve consistency of a slab temperature throughouta thickness of the slab, which in turn may facilitate molding of theslab without substantial cracks, blemishes, etc. Curved slabs may thushave a combination of larger slab thickness, larger particulate sizesand/or smaller radii of curvature while providing a pleasing aestheticappearance.

Third, pre-manufactured slabs may increase manufacturing efficiency byrequiring fewer mold types, shapes, etc. in vibration and compactionoperations that may be used during initial manufacturing of the slabs.For example, a single mold (e.g., having a standard or common moldshape) may be used for fabrication of slabs from raw materials, whileone or more thermoforming methods described herein may be used tocustomize the slabs into curved slabs having multiple different threedimensional curves and shapes.

Fourth, the methods and systems described herein facilitate formingslabs to a range of shapes and curvatures while requiring less time andresources. For example, a heating device (e.g., a conductive heatingpad) may readily be positioned to apply heat to a slab during a moldingoperation and subsequently removed without generating substantial wastematerials.

Fifth, the methods and systems described herein may facilitateautomation or semi-automated methods. For example, a slab may be loadedinto a system which carries out one or more operations with limitedmanual intervention to impart a curved surface to the slab.

Sixth, the methods and systems described herein facilitate thermoformingat a manufacturing location or a remote location such as a fabricationlocation or an installation location. Substantially planar slabs may bereadily transported to a fabrication or installation location (e.g.,such that many slabs may be efficiently transported in a relativelysmall volume), and subsequently formed to impart a desired curve.

The details of one or more implementations are set forth in theaccompanying drawings and the description below. Other features andadvantages will be apparent from the description and drawings, and fromthe claims.

DESCRIPTION OF DRAWINGS

FIG. 1 is a plan view of an exemplary system for thermoforming a curvedslab having a single semi-circular curve.

FIG. 2 is a plan view of an exemplary system for thermoforming a curvedslab having two adjacent curves.

FIG. 3 is a plan view of an exemplary system for thermoforming a curvedslab having more than one curve.

FIG. 4A is a perspective view of an exemplary slab prior to undergoing athermoforming method.

FIG. 4B is a perspective view of the slab of FIG. 4A after undergoing anexemplary thermoforming method.

FIG. 5 is a perspective view of an exemplary slab that includescurvature about multiple axes.

FIG. 6 is a flow diagram of an example method of thermoforming a slab.

DETAILED DESCRIPTION

Referring to FIG. 1, an exemplary system 100 that may be used to form acurved slab (e.g., bent, arced, angled, undulating, arcuate, orotherwise non-planar surfaces) is shown. System 100 includes a mold 150and a heating device, such as heating devices 161, 162, configured togenerate heat for application to a slab. Mold 150 includes a surfacehaving a shape that can be imparted to the slab by positioning the slabon the surface of the mold 150 and applying heat to the slab from theheating device. For example, mold 150 includes a curved surface 151(e.g., having a semi-circular curve) that a slab may be conformed to.

Slab 101 (e.g., an uncut slab or a portion of a slab) is located atleast partially on mold 150 such that a curvature of mold 150 may beimparted to slab 101. In an exemplary embodiment, slab 101 has a firstmajor surface 121, a second major surface 122, and a thickness 115separating the first major surface 121 and the second major surface 122.In an exemplary embodiment, slab 101 is supported entirely on mold 150.Alternatively or additionally, slab 101 may be supported by one or moresupport devices (e.g., while mold 150 functions primarily to provide ashaped surface).

The heating device of system 100 is configured to warm slab 101 to amoldable temperature sufficient to facilitate deformation and/or moldingof slab 101 to the outer curvature of mold 150. In an exemplaryembodiment, the heating device includes one or more conductive heatingdevices 161, 162. The conductive heating devices 161, 162 are positionedproximate slab 101 to deliver (e.g., directly or indirectly via one ormore intermediate layers) conductive heat to slab 101. In some exemplaryembodiments, the heating device may include a first conductive pad 161and a second conductive pad 162. For example, first conductive pad 161may be situated adjacent to the first major surface 121 of slab 101 andbetween slab 101 and mold 150. Second conductive pad 162 may be situatedadjacent to the second major surface 122 of slab 101.

Alternatively or additionally, the heating devices may deliver heat toslab 101 via radiant and/or convective heat transfer modes. For example,the heating devices may deliver heat by microwave radiation, one or moreheating elements spaced from the slab, a liquid bath or shower (e.g.,water, oil, etc.), forced convective fluid flow (e.g. non-liquidconvective fluid, liquid convective fluid, air from a fan or blower,etc.), etc. Such heating modes can facilitate heat transfer throughout athickness of the slab, and can be applied to one or both major surfacesof the slab simultaneously. In some embodiments, heat can be applied toone or both major surfaces while the slab is shaped to a mold surface.In various exemplary embodiments, application of heat in this manner canfacilitate a relatively small radius of curvature.

The heating device may be configured to deliver heat to a substantialportion of first and second major surfaces 121, 122, respectively. Forexample, first conducting heating device 161 may be configured todeliver heat via contact with (e.g., directly or indirectly via one ormore intermediate layers) more than 50%, more than 75%, more than 85%,more than 90%, more than 95%, or all of first major surface 121 of slab101. Alternatively or additionally, second conducting heating device 162may be configured to deliver heat via contact with more than 50%, morethan 75%, more than 85%, more than 90%, more than 95%, or all of secondmajor surface 122 of slab 101. Delivery of heat to substantial portionsof first and/or second surfaces 121, 122 may facilitate rapid andconsistent heating of slab 101, and in turn promote rapid forming ofslab 101.

The heating device may include heating device portions that areindependently positionable with respect to one another and/or withrespect to the mold 150. For example, first conductive pad 161 may bepositionable on slab 101 or mold 150 independently of second conductivepad 162 (e.g., such that first conductive pad 161 is adjacent firstmajor surface 121 and second conductive pad 162 is adjacent second majorsurface 122). In other exemplary embodiments, first conductive pad 161and second conductive pad 162 may be connected together and formportions of a unitary heating device. For example, the heating devicemay be foldable (e.g. around a thickness of slab 101) such that firstconductive pad 161 is adjacent first major surface 121 and secondconductive pad 162 is adjacent second major surface 122 of slab 101while first and second conductive pads 161, 162 are joined to oneanother (e.g., and share one or more conductive elements).

In some embodiments, one or both of first and second conductive heatingdevices 161, 162 may be attached or embedded in mold 150. For example,first conductive heating pad may form at least a portion of curvedsurface 151 or be attached to an outer or inner face of curved surface151. In some embodiments, mold 150 is made from a substantiallyinsulative material such as wood, fiberglass, ceramic, plaster, cement,stone, etc. Alternatively or additionally, one or more portions of mold150 may be thermally conductive to facilitate heat transfer to slab 101(e.g., curved molding surface 151 may be a thermally conductive metal,such as when heating device 161 is located on an internal face of curvedmolding surface 151, or when two or more conductive heating pads areused on the same molding surface).

In some embodiments, slab 101 can be secured to mold 150, such as by oneor more clamps 170. Clamps 170 may be configured to maintain slab 101 ina particular position and/or orientation relative to mold 150 (e.g.,during a molding operation). Alternatively or additionally, clamps 170may act on slab 101 to conform slab 101 to a shape of mold 150. Forexample, clamps 170 may apply a force on slab 101 so that slab 101conforms to a shape of mold 150. In various exemplary embodiments,clamps 170 may include one or more of a parallel-type clamp, a bar-typeclamp, a pneumatic clamp, hydraulic clamp, or the like that can bendand/or maintain slab 101 in a position relative to mold 150.

The heating devices may provide continuous heating to slab 101. In someembodiments, a single conductive pad, such as first conductive pad 161,can provide continuous heating to slab 101 (e.g., while slab 101 isformed to mold 150) to elevate the temperature of slab 101 throughoutthe entire thickness of slab 101. A conductive pad maintained inconstant contact (e.g., directly or indirectly) with slab 101facilitates consistent heating of slab 101. In some embodiments, two ormore conductive pads, such as first conductive pad 161 and secondconductive pad 162 can, together, provide continuous heating to slab 101(e.g., while slab 101 is formed to mold 150), to elevate the temperatureof slab 101 throughout the entire thickness of slab 101. First andsecond conductive pads positioned adjacent first and second majorsurfaces 121, 122 of slab 101 facilitate rapid and consistent heating ofslab 101. The temperature of slab 101 may be substantially consistentwithin a relatively controlled range throughout the entire thickness ofslab 101. Such heating may facilitate precise temperature control ofslab 101, and an efficient molding operation. Alternatively oradditionally, system 100 having conducting heating devices 161, 162, forexample, can facilitate molding a slab 101 that is not heated prior toplacing on mold 150 (e.g., the slab is at room temperature when placedon the mold 150).

In some embodiments, mold 150 is configured to form a curve into slab101 having a radius of curvature 180. The radius of curvature 180 is theradius of an imaginary circle 181 that approximately fits the curve ofslab 101 produced by mold 150. Slab 101 may be formed such that thecurve has a consistent radius of curvature along the curve. In otherembodiments, slab 101 may be formed such that the curve is a complexcurve having a radius of curvature that varies along the curve. Radiusof curvature 180 may be a minimum radius of curvature along the entirecurve.

Referring to FIG. 2, a mold can include two or more curved shapes, suchas in the exemplary system 200 for thermoforming a slab. In someembodiments, system 200 may include features similar to system 100described above. System 200 may include a mold 250 and a heating device,such as heating devices 261, 262. Mold 250 includes surfaces definingtwo or more curved shapes spaced from one another that can be impartedto a slab by conforming the slab to the surfaces of the mold 250.

Slab 201 has a first major surface 221, a second major surface 222, anda thickness 215 separating the first major surface 221 and the secondmajor surface 222. First and second surfaces 221, 222 may be curved toconform to a shape of mold 250. In an exemplary embodiment, slab 201 issupported entirely on mold 250. Alternatively or additionally, slab 201may be supported by one or more support devices (e.g., while mold 250functions primarily to provide shaped surfaces).

The heating devices of system 200 are configured to warm slab 201 to amoldable temperature to facilitate deformation and/or molding of slab201 to a shape of mold 250. In an exemplary embodiment, the heatingdevice includes one or more conductive heating devices 261, 262. Theconductive heating devices are positioned proximate slab 201 to deliver(e.g., directly or indirectly via one or more intermediate layers)conductive heat to slab 201. In some exemplary embodiments, the heatingdevice may include a first conductive pad 261 and a second conductivepad 262. For example, first conductive pad 261 may be situated adjacentto the first major surface 221 of slab 201 and between slab 201 and mold250. Second conductive pad 262 may be situated adjacent to the secondmajor surface 222 of slab 201.

In an exemplary embodiment, mold 250 is configured to impart two curvedshapes to slab 201. Mold 250 includes a first curved molding surface 251having a first radius of curvature 280, wherein the first radius ofcurvature 280 is the radius of a first imaginary circle 281 thatapproximately fits at least a portion of the first curve of slab 201produced by mold 250. Mold 250 includes a second curved molding surface252 having a second radius of curvature 282, wherein the second radiusof curvature 282 is the radius of a second imaginary circle 283 thatapproximately fits at least a portion of the second curve of slab 201produced by mold 250. The first curved molding surface 251 of mold 250defining the first radius of curvature 281 may be spaced from the secondcurved molding surface 252 of mold 250 defining the second radius ofcurvature (e.g., spaced along a length and/or width of mold 250). Forexample, an intermediate portion 253 may be present between first andsecond curved molding surfaces 251, 252.

The heating device may include portions that are positionableindependently of one another. For example, first conductive pad 261 maybe positionable on slab 201 or mold 250 independently of secondconductive pad 262 (e.g., such that first conductive pad 261 is adjacentfirst major surface 221 and second conductive pad 262 is adjacent secondmajor surface 222). In other exemplary embodiments, first conductive pad261 and second conductive pad 262 may be connected together and formportions of a unitary heating device. For example, the heating devicemay be foldable (e.g. around a thickness of slab 201) such that firstconductive pad 261 is adjacent first major surface 221 and secondconductive pad 262 is adjacent second major surface 222 of slab 201while first and second conductive pads 261, 262 are joined to oneanother (e.g., and share one or more conductive elements).

In an exemplary embodiment, first conductive pad 261 may deliver heat atlocations of each curved shape. For example, the first conductive pad261 extends along substantially all of first major surface 221 of slab201 including an intermediate location between each curved shape.Alternatively or additionally, second conductive pad 262 may deliverheat at locations of each curved shape. For example, the secondconductive pad 262 extends along substantially all of second majorsurface 222 of slab 201 including the intermediate portion 253 betweeneach curved surface. Such a configuration may facilitate consistentheating of slab 201 such that slab 201 may readily conform to mold 250and/or facilitate curves in two different directions.

In some embodiments, the slab 201 may be heated with different heatingdevices (e.g., heated independently) at the location of each curvedsurface. For example, only first conductive pad 261 may be used todeliver heat to slab 201 proximate the first curved molding surface 251,and only the second conductive pad 262 may be used to deliver heat toslab 201 proximate the second curved molding surface 252. System 200 mayfurther include third and fourth conductive heating pads such that firstand second major surfaces are heated proximate the first and secondcurved molding surfaces 251, 252. In some embodiments, an intermediateportion 253 between the first and second curved molding surfaces 251,252 is not directly heated (e.g., and is maintained at a relativelylower temperature than the locations of the curved shapes during amolding operation).

Curved slab 201 may be suitable for use as a countertop, table,flooring, wall, column, faux column, cladding, bath or shower surround,sink, or other building material application. In some embodiments, acurved slab 201 have multiple curved locations may provide a unitarycountertop having surfaces of different heights. For example, a firstportion of the slab 201 may provide a countertop surface at a relativelytaller height, and a second portion of the slab 201 may provide acountertop surface at a relatively shorter height. Curved slab 201 maythus provide a unitary, continuous surface having two or more countertopsurface heights, while reducing the appearance of joints or seams, andassociated seaming operations, that may otherwise be required.

Referring to FIG. 3, an exemplary system 300 is shown for forming one ormore curves in a slab 301. System 300 includes a mold 350 and a heatingdevice, such as heating devices 361, 362. Mold 350 can, in someembodiments, be used to impart a first curve 391 to a first portion ofthe slab, then moved to a second portion of the slab to impart a secondcurve on a second portion of the slab. In other embodiments, two or moremolds may be used at the same time, or at different times, on differentportions of the same slab, to impart multiple curves on the same slab.In some embodiments, system 300 may include features similar to systems100, 200 described above.

System 300 may be used to impart a curve in slab 301 (e.g., after slab301 already includes a curved surface 391). For example, slab 301includes a first curve 391, having a first radius of curvature 380 thatis the radius of first imaginary circle 381. First curve 391 waspreviously formed in slab 301, for example, by an exemplary methoddescribed herein. Mold 350 includes a curved molding surface 351 thatslab 301 is formed around to generate second curved surface 392.

The heating device of system 300 is configured to warm a portion of slab301 (e.g., a portion of slab 301 not including curved surface 391) to amoldable temperature sufficient to facilitate deformation and/or moldingof slab 301 to curved molding surface 351 of mold 350. In an exemplaryembodiment, the heating device includes one or more conductive heatingdevices 361, 362 situated adjacent to the first major surface 321 andsecond major surface 322, respectively, of slab 301. Conductive heatingdevices may be configured to deliver heat only proximate curved surface392, and not deliver heat to other portions of slab 301. Delivery ofheat to first and second major surfaces 321, 322 of slab 301 onlyproximate curved surface 392 facilitates consistent heating at thelocation of curved surface 392 while maintaining the temperature of slab301 below a moldable temperature to avoid inadvertent deformation ofslab 301.

In an exemplary embodiment, slab 301 is not supported entirely on mold350. Mold 350 may primarily function to provide a curved molding surface351 that slab 301 may be conformed to, while one or more support devicessupport slab 301. Mold 350 may be readily positionable relative to slab301 to form curved surface 392 at a desired location on slab 301, suchas a desired location along a length of slab 301. Mold 350 may thus beused to generate multiple slabs 301 having a variety of configurationsby positioning mold 350 at different locations on the slabs 301, and toform additional curved surfaces in slabs 301 that already include one ormore curved surfaces.

Referring now to FIG. 4A, an exemplary stone slab 401 is shown thatincludes a planar first major surface 421 and a planar second majorsurface 422 separated by a thickness 415. Stone slab 401 may beprocessed and/or cut to have a length L and a width W, as desired for aparticular application. For example, stone slab 401 may be a relativelylarge slab that may be cut to specific shapes for use in living orworking spaces (e.g., along a countertop, table, floor, or the like). Invarious exemplary embodiments, stone slab 401 is at least 3 feet wide byat least 6 feet long, for example between about 3 feet and 18 feet wideand between about 6 feet and 24 feet long, or between about 4.5 feet and7 feet wide and between about 10 feet and 12 feet long. In someexemplary embodiments, stone slab 401 is about 7 feet wide by about 12feet long. In other embodiments, stone slab 401 is about 4.5 feet wide(approximately 140 cm wide) by about 10 feet long (approximately 310 cmlong). In some embodiments, stone slab 401 may be a relatively smallslab or slab strip (e.g. having a relatively small width and relativelylarge length). Small slabs or slab strips may facilitate applications asmolding, mitered edges, or other installation locations where a smallslab may be appropriate. The slab strip 401 may be curved to complementa relatively large slab, installation environment, or impart aparticular aesthetic appearance. In some embodiments, one or more curvesmay be imparted on all of stone slab 401. In some embodiments, one ormore curves may be imparted on one or more portions of stone slab 401.In some exemplary embodiments, stone slab 401 has rectangular edges, orcan be mitered or otherwise processed to include various edge profiles,such as bullnose, half bullnose, waterfall, reverse waterfall, doublepencil, mitered edge, shale edge, cornice, ledge, ogee, bevel, anglecut, round double, eased, or other edge profile.

In some embodiments, the thickness 415 of the slab 401 is at least about0.01 inches, at least 0.2 inches, between about 0.01 inches and about 5inches, between about 0.1 inches and about 3 inches, between about 0.1inches and about 1 inch, or between about 0.25 inches and about 2.0inches. In some embodiments, the thickness 415 of the slab is betweenabout 0.1 and about 0.75 inches, between about 0.1 and about 0.5 inches,or between about 0.1 inches and about 0.25 inches.

Referring now to FIG. 4B, exemplary slab 401 is shown after being curvedto form a curved slab 401. Curved slab 401 includes a first majorsurface 421 separated from a second major surface 422 by a slabthickness 415. First and second major surfaces 421, 422 exhibit curvedshapes defined by one or more radii of curvature.

In some embodiments, a stone slab having a thickness of between about0.1 inches and about 2.0 inches can be formed to molds producing radiiof curvature between about 18 inches and about 100 inches. In someembodiments, a stone slab having a thickness of between about 0.1 inchesand about 1.0 inches can be formed to molds producing radii of curvaturebetween about 36 inches and about 100 inches. In some embodiments, astone slab having a thickness of between about 0.1 inches and about 1.5inches can be formed to molds producing radii of curvature between about60 inches and about 100 inches. In some embodiments, a stone slab havinga thickness of between about 0.5 inches and about 3 inches can be formedto molds producing radii of curvature between about 80 inches and about100 inches.

In some embodiments, stone slabs described herein may be attached with asupport backing. For example, a first surface of the stone slab may be apolished surface having a desired aesthetic appearance, and a secondsurface of the stone slab may be adhered to the support backing. Thesupport backing may include a relatively lightweight structural backingthat provides additional strength and support to the stone whileremaining lighter than a stone slab without the structure backing havingthe same thickness as the support backing. The support backing may allowthinner stone slabs to be used, and can provide reduced weight of stoneused, in a given application. Exemplary support backing materials caninclude metal, fiberglass, or any material that is lighter than a stoneslab having the same thickness as the support backing and can providestructural support to the stone slab. The support backing may include alattice structure that supports the stone slab and reduces theoccurrence of cracking, breaking, etc. In some embodiments, the supportbacking at least partially maintains the stone slab in a curved shape.In some embodiments, the support backing can provide protection to thestone slab during shipping, installation, or use. The stone slab can beaffixed to the support backing using an adhesive, such as a glue,adhesive tape, mechanical fasteners, or the like. The support backingmay allow the stone slab to be used in a variety of applications thatmay require or benefit from a lightweight structure, such as wallcoverings, veneers, automotive applications, etc.

In some embodiments, the support backing can be a part of the stone slabbefore undergoing any of the methods described herein (e.g., such thatthe stone slab and support simultaneously undergo bending/molding toproduce the curved slab). For example, applying heat to the stone slab,and/or continuously heating the stone slab, may include applying heat toand/or continuously heating a major surface of a support backing.Alternatively or additionally, the stone slab may be curved or partiallycurved before being joined with the support backing.

In various exemplary embodiments, curved slabs 401 may include processedstone slabs, tiles, partial stone slabs, etc. For example, processedstone slabs can include organic polymer(s) and inorganic (mineral)particulate components. The inorganic (mineral) particulate componentmay include such components as silicon, basalt, glass, diamond, rocks,pebbles, shells, a variety of quartz containing materials, such as, forexample, but not limited to: crushed quartz, sand, quartz particles, andthe like, or any combination thereof. In some embodiments, theparticulate mineral components comprise a quartz material as apredominant component, which may include sand of various particle sizesand of different combinations.

In a hardened slab, the organic and inorganic materials can be linkedusing a binder, which may include for example, mono-functional ormultifunctional organosilane molecules, dendrimeric molecules, and thelike, that may have the ability to bind the organic and inorganiccomponents of the composite stone mix. The binders may further include amixture of various components, such as initiators, hardeners, catalysts,binding molecules and bridges, or any combination thereof. In someembodiments, the slabs may include about 80-95% quartz aggregates toabout 5-15% polymer resins. In addition, various additives, may bepresent, including metallic pieces (e.g., copper flecks or the like),colorants, dyes, pigments, chemical reagents, antimicrobial substances,fungicidal agents, and the like, or any combination thereof.

In some embodiments, the particles (e.g., mineral particulatecomponents) present in the composite stone mix have a particle size ofless than about 0.2 inches. In some embodiments, the particles range insize from about 0.0001 inches to about 0.2 inches, from about 0.0002inches to about 0.08 inches, from about 0.0002 inches to about 0.07inches, from about 0.00025 inches to about 0.01 inches, or from about0.0002 inches to about 0.002 inches. In some embodiments, suchrelatively small particle sizes facilitate a small radius of curvaturewithout cracking, blemishes, or loss of particulate matter in a finishedcurved slab.

In some embodiments, particle size, slab thickness, and radius ofcurvature of curved shapes of the slab may be selected to produce acurved slab having beneficial characteristics. In some embodiments,exemplary slabs may have thicknesses between about 0.01 inches and about4 inches, one or more curves having radii between about 50 inches toabout 100 inches, and particle sizes up to about 0.05 inches, 0.1inches, 0.15 inches, or up to about 0.2 inches or more. In anotherexemplary embodiment, exemplary slabs may have slab thicknesses betweenabout 0.1 inches to about 0.25 inches, one or more curves having radiibetween about 18 inches and about 100 inches or more, and particle sizesless than about 0.0001 inches, 0.0005 inches, or less than about 0.001inches.

In some embodiments, the starting material for the methods and systemsdescribed herein include previously formed, hardened, processed stoneslabs. For example, a slab may be fully formed such that the particulatematerial, binder, and other components of the slabs have previously beensubject to vibration, compression molding, compaction, curing,thermoforming, and/or combinations thereof, to produce a hardened slab.The slab may be thermoformed in a subsequent operation to impart one ormore curved shapes to the slab. Thus, in some exemplary methodsdescribed herein, the slab has been previously compacted, compressed,cured, thermoformed, or any combination thereof, prior to heating theslab in a forming operation (e.g., on a mold having a curved moldingsurface). In some embodiments, the methods for thermoforming describedherein are thus methods of post-forming stone slabs that havesubstantially planar major surfaces.

Alternatively or additionally, a slab may be formed to have one or morecurved surfaces as part of the original manufacturing operation orimmediately following original manufacturing (e.g., at the same facilitywhere initial manufacturing occurs, or at the end of the manufacturingline where original manufacturing occurs). In some embodiments, a slabmay be thermoformed before the slab has fully cooled from an initialmanufacturing operation. Thermoforming immediately following an initialmanufacturing line may reduce energy usage by reducing the heat requireddue to the slab already being at an elevated temperature, and/or byreducing handling and transportation (e.g., transportation to a remotelocation in order to conduct the thermoforming operation).

In an exemplary embodiment, an original manufacturing process of forminga slab may include an operation of dispensing one or more pigmentedparticulate mineral mixes into a mold to generate a slab having adesired aesthetic appearance. After the mold has been sufficientlyfilled, the mold may be moved to one or more subsequent operations, suchas a vibro-compaction press operation during which compaction pressure,vibration, and/or vacuum may be applied to the contents inside thefilled mold, thereby converting the one or more particulate mixes into arigid slab. After a vibro-compaction operation, the filled mold (withthe compacted and hardened slab therein) may proceed to a curingoperation during which the material used to form the slab (including anyresin binder material) are cured via a heating or other curing process,thereby further strengthening the slab inside the filled mold. After theslab is fully cured and sufficiently cooled, the hardened and cured slabmay be removed from the mold at a mold removal operation. In someembodiments, the slab may be thermoformed after the curing processbefore the slab has fully cooled to impart one or more curved surfaces,as described herein. The method may further include a finishingoperation, during which a major surface of the slab is finished, such asby polishing to a smooth finish, or otherwise imparting a polished,matte, honed, raw, or other finish.

Referring now to FIG. 5, an exemplary stone slab 501 is shown thatincludes a first major surface 521 and a second major surface 522separated by a thickness 515. Stone slab 501 includes multiple complexcurved portions imparted by a mold (e.g. as described herein). Thecurved portions may be defined by one or more radii of curvature, suchthat a radius of curvature varies across a particular curve.Alternatively or in addition, the curved portions can curve aboutdifferent axes. For example, a first curved portion 523 may include acurve about an axes A that is substantially vertical, and a secondcurved portion 524 may include a curve about an axis B that is angledfrom vertical. A stone slab have complex curvature (e.g. formed asdescribed herein) may promote an organic appearance and/or facilitate aprecise shape suitable for a particular installation location.

Referring to FIG. 6, a flow diagram of an exemplary method 600 forthermoforming a stone slab is shown, including applying heat to theslab, and forming the slab around a mold while continuously applyingheat to the slab. In some optional embodiments, the method can beginimmediately after processed stone slab has come off the manufacturingline. For example, a processed stone slab can be produced from compositemixes, such as those described herein, by mixing the components, pouringthe mixture into a mold, and compacting, vibrating, curing,thermoforming, or otherwise solidifying the slab. Then, the newlyfabricated slab can move directly from the production line to a mold asdescribed herein for thermoforming the slab to have one or more curves.In some embodiments, the slab can optionally be further processed, suchas by cutting, mitering, edge finishing, surface finishing, polishing,or other processing, prior to thermoforming the slab to have one or morecurves. In some embodiments, the slab can optionally be furtherprocessed, such as by cutting, mitering, edge finishing, surfacefinishing, polishing, or other processing, after thermoforming the slabto have one or more curves. In some embodiments, hardened processedslabs can be molded to have one or more curves at a location remote fromthe production line. For example, a processed stone slab can be producedfrom composite mixes, such as those described herein, by mixing thecomponents, pouring the mixture into a mold, and compacting, vibrating,curing, thermoforming, or otherwise solidifying the slab, and thenstored for some time and/or shipped to a remote location, such as awarehouse, distributor, or installation site. Then the slab can bethermoformed on a mold to form one or more curves in the slab. The slabmay be optionally further processed, such as by cutting, mitering, edgefinishing, polishing, or other processing, before or after storage orshipping, and before or after thermoforming the slab to have one or morecurves. The methods described herein advantageously allow flexibility inwhere the curve thermoforming can take place, as the use of conductiveheat sources such as conductive pads allows for portability.

Exemplary method 600 may include operation 605 of applying heat to aslab positioned on a mold. In some embodiments, the slab may havefeatures similar to slabs 101, 201, 301, 401 and/or 501, etc. describedherein. Applying heat to the stone slab may include applying conductiveheat to the slab, such as directly or indirectly applying conductiveheat using a positionable conductive heating pad, resistive heatingwires, or other heating element that conductively transfers heat to theslab. For example operation 605 of applying heat can includecontinuously heating a first conductive pad positioned on the firstmajor surface of the slab (e.g., by modulating current through aresistive heating element of the conductive pad).

In some embodiments, operation 605 of applying heat can include heatinga second conductive pad positioned on the second major surface of theslab simultaneously with the first conductive heating pad. Applying heatsimultaneously to first and second major surfaces of the stone slab mayfacilitate a consistent temperature through an entire thickness of thestone slab, and may facilitate a reduced heating time required for theslab temperature to rise to a temperature sufficient for molding of theslab.

In an exemplary embodiment, operation 605 of applying heat to the slabincludes heating the slab from ambient temperature after the slab isplaced on the mold. For example, the slab may not be pre-heated suchthat the slab is at ambient temperature when placed on the mold.Applying heat to raise a temperature of the slab to a moldabletemperature may thus be performed entirely while the slab is on themold. In other exemplary embodiments, the slab may be preheated to anelevated temperature before being placed on the mold. Operation 605 ofapplying heat may include continuously applying heat to maintain a slabtemperature at a moldable temperature while the slab is conformed to asurface of the mold.

In various exemplary embodiments, operation 605 of applying heat to theslab may, alternatively or additionally, include non-conductive modes ofheating, including radiant heating and/or convective heating modes. Forexample, operation 605 may include applying heat by microwave radiation,one or more heating elements spaced from the slab, a liquid bath orshower (e.g., water, oil, etc.), forced convective fluid flow (e.g.non-liquid convective fluid, liquid convective fluid, air from a fan orblower, etc.), etc. Such heating modes can facilitate heat transferthroughout a thickness of the slab, and can be applied to one or bothmajor surfaces of the slab simultaneously. In some embodiments,operation 605 can include applying heat by one or more heating modes toone or both major surfaces of the slab while the slab is shaped to amold surface. In various exemplary embodiments, applying heat in thismanner can facilitate a relatively small radius of curvature.

Operation 605 of applying heat to the slab includes applying heat tomaintain a temperature of at least a portion of the slab at a moldabletemperature at which the slab may bend and conform to a shape of themold without cracking. In an exemplary embodiment, a moldabletemperature may be determined based on a surface temperature of the slab(e.g., and the temperature of the heating pad). Alternatively oradditionally, a moldable temperature may be determined based on aninternal temperature of the slab. Thus, heating devices can becontrolled based on a measured or calculated temperature of one or moreof a temperature of a portion of a major surface of the slab, aninternal temperature of a portion of the slab, a temperature of at leasta portion of a heating device (e.g. the first and second conductivepads), and/or a temperature to which a heating device has been set. Insome embodiments, a heating mechanism may operate cyclically to heat andmaintain a temperature setting (e.g., by modulating an electricalcurrent through a resistive heating element). Thus the temperaturesdescribed herein, as well as the operation of applying heat and/orcontinuously heating described herein, can include periods of minimaltemperature changes as the heating mechanism cycles on and off tomaintain a set temperature. In some embodiments, temperatures describedherein refer to average temperatures of a slab portion, slab surfaceportion, internal slab portion, heating mechanism portion, or the like,across a period of time for which a heating mechanism is heating orcontinuously applying heat.

In some embodiments, a curve may be desired on only a portion of a slab,and operation 605 of applying heat to the slab may include continuouslyapplying heat only to a selected portion of the slab that is intended tobe molded. The portion of a slab that is being molded may exhibitdiffering temperatures across one or more surfaces of the portion of theslab, or throughout the thickness of the portion of the slab beingmolded, while being maintained at or near a moldable temperature.

Operation 605 of applying heat may include applying heat for a period oftime sufficient to reach a moldable temperature, for example, atemperature that renders the slab moldable. In some embodiments, whenheated to its moldable temperature, the slab can bend to produce acurve, for example a curve having a radius of curvature of less than 100inches, such as between 18 inches and 100 inches, 23 inches and 80inches, 36 inches and 72 inches, or about 50 inches, without visiblebreakage or cracks. In some embodiments, a moldable temperature caninclude a temperature ranging from about 30° C. to about 200° C., 50° C.to about 150° C., or about 100° C.

In some embodiments, the moldable temperature is related to a glasstransition temperature (Tg) of the slab, such as a glass transitiontemperature (Tg) of a resin binder or one or more other components ofthe slab. Tg can be measured by any of the standard processes formeasuring Tg, such as by differential scanning calorimetry (DSC),thermal mechanical analysis (TMA), or dynamic mechanical analysis (DMA).Standard protocols such as ASTM E1640-13, ASTM E1545-11, ASTM E2602-09,ASTM E1356-08, ASTM D7028, or the like may be used. In some embodiments,a moldable temperature can include a temperature or range oftemperatures at or below the Tg. For example, the moldable temperatureto which the slab is heated may be maintained within a selecteddeviation from the glass transition temperature to avoid affecting thestructural characteristics of the final slab. The slab can thus beheated, molded, and cooled to impart a curved surface without adverselyaffecting the structural characteristics of the slab by controllingapplication of heat within a desired range of the glass transitiontemperature Tg.

In some embodiments, a moldable temperature can include a temperaturewithin 5° C. of the Tg of one or more components of the slab, within 15°C., within 20° C., or within 35° C. of the Tg of one or more componentsof the slab. In some embodiments, a moldable temperature can include analtered Tg of a polymer component or resin binder of the slab. Forexample, while a specific polymer has a first Tg, binding of theparticulate matter to the polymer, copolymerization, and addition ofplasticizers, hardeners, initiators, or other additives can alter the Tgof the polymer. In some embodiments, a moldable temperature can includea temperature within 5° C. of the Tg of one or more components of theslab, within 15° C., within 20° C., or within 35° C. of the altered Tgof one or more components of the slab.

In some embodiments, the moldable temperature is related to a Vicatsoftening point of the slab, such as a Vicat softening point of a resinbinder or one or more other components of the slab. As used herein, theVicat softening point temperature describes a temperature at which anamorphous material changes from a brittle vitreous state to a plastic,deformable, flexible, or viscous state. The Vicat softening pointtemperature can be measured by standard protocols such as ASTM-D1525,ISO 306, or the like. In some embodiments, the Vicat softening point ofthe slab or of a component of the slab can be at or below the Tg of theslab or component of the slab. In some embodiments, a moldabletemperature can include a temperature or range of temperatures at orabove the Vicat softening point of the slab or a component of the slab.For example, the moldable temperature to which the slab is heated may bemaintained within a selected deviation above the Vicat softening pointtemperature but below the glass transition temperature Tg of the slab toavoid affecting the structural characteristics of the final slab. Theslab can thus be heated, molded, and cooled to impart a curved surfacewithout adversely affecting the structural characteristics of the slabby controlling application of heat within a desired range above theVicat softening point but below the glass transition temperature Tg.

In some embodiments, a moldable temperature can include a temperature ator up to 5° C. above the Vicat softening point temperature of one ormore components of the slab, up to 15° C. above, up to 20° C. above, orup to 35° C. above the Vicat softening point temperature of one or morecomponents of the slab. In some embodiments, a moldable temperature caninclude an altered Vicat softening point temperature of a polymercomponent or resin binder of the slab. For example, while a specificpolymer has a first Vicat softening point temperature, binding of theparticulate matter to the polymer, copolymerization, and addition ofplasticizers, hardeners, initiators, or other additives can alter theVicat softening point temperature of the polymer. In some embodiments, amoldable temperature can include a temperature at or up to 5° C. abovethe altered Vicat softening point temperature of one or more componentsof the slab, up to 15° C. above, up to 20° C. above, or up to 35° C.above the altered Vicat softening point temperature of one or morecomponents of the slab.

In some embodiments, the moldable temperature is related to a heatdeflection temperature or heat distortion temperature (HDT) of the slab,such as the HDT of a resin binder or one or more other components of theslab. As used herein, the HDT describes a temperature at which a polymeror plastic sample deforms under a specified load. The HDT can bemeasured by standard protocols such as ASTM-D648, ISO 75, or the like.In some embodiments, the HDT of the slab or of a component of the slabcan be at or below the Tg of the slab or component of the slab. In someembodiments, a moldable temperature can include a temperature or rangeof temperatures at or above the HDT of the slab or a component of theslab. For example, the moldable temperature to which the slab is heatedmay be maintained within a selected deviation above the HDT but belowthe glass transition temperature Tg of the slab to avoid affecting thestructural characteristics of the final slab. The slab can thus beheated, molded, and cooled to impart a curved surface without adverselyaffecting the structural characteristics of the slab by controllingapplication of heat within a desired range above the HDT but below theglass transition temperature Tg.

In some embodiments, a moldable temperature can include a temperature ator up 5° C. above the HDT of one or more components of the slab, up to15° C. above, up to 20° C. above, or up to 35° C. above the HDT of oneor more components of the slab. In some embodiments, a moldabletemperature can include an altered HDT of a polymer component or resinbinder of the slab. For example, while a specific polymer has a firstHDT, binding of the particulate matter to the polymer, copolymerization,and addition of plasticizers, hardeners, initiators, or other additivescan alter the HDT of the polymer. In some embodiments, a moldabletemperature can include a temperature at or up to 5° C. above thealtered HDT of one or more components of the slab, up to 15° C. above,up to 20° C. above, or up to 35° C. above the altered HDT of one or morecomponents of the slab.

Method 600 further includes operation 606 of forming the slab to themold while continuously heating the slab. In some embodiments, forming aslab to a mold can include conforming the slab to the shape of anexternal dimension of a mold. Forming the slab to a mold can, in someembodiments, include forming the slab to a mold while simultaneouslyapplying the conductive heat to the first and second major surfaces. Forexample, operations 605 and 606 may be performed at least partiallysimultaneously such that the slab is heated and molded to a shape of themold at the same time.

The slab may be maintained at a moldable temperature until the slab hascompletely conformed to the shape of the mold. In some embodiments, aperiod of time sufficient to allow the slab to conform to a moldincludes from about 1 minute to about 240 minutes.

Operation 606 of forming the slab to the mold may, in some embodiments,include forming one or more curves having a radius of curvature definedas the radius of an imaginary circles that approximately fits the curve.In some embodiments, forming a slab to a mold includes forming a curvehaving a minimum radius of curvature of less than about 100 inches. Insome embodiments, forming a slab to a mold includes forming a curvehaving a minimum radius of curvature of about 18 inches or greater,about 20 inches or greater, about 22 inches or greater, or about 25inches or greater. In some embodiments, forming the slab to the moldincludes forming a curve having a minimum radius of curvature from about18 inches to about 100 inches. In some embodiments, forming a slab to amold includes forming a curve having a minimum radius of curvature ofgreater than about 100 inches. In some embodiments, forming a slab to amold includes forming a curve having a minimum radius of curvature ofbetween about 20 inches to about 80 inches, from about 23 inches toabout 70 inches, from about 30 inches to about 60 inches, or from about40 inches to about 50 inches. In some embodiments, operation 606 offorming the slab to the mold includes forming a curve having a minimumradius of curvature from about 20 inches to about 90 inches, from about50 inches to about 90 inches, or from about 60 inches to about 80inches.

The weight of a slab may, in some embodiments, provide sufficientpressure to conform the slab, at a moldable temperature, to a moldwithout requiring additional pressure. In some embodiments, additionalpressure may be applied to conform a slab, at a moldable temperature, toa mold, or to hold a slab in place on a mold while heating or coolingthe slab. Exemplary additional pressure that can be applied to the slabto conform the slab to the mold can include weights, clamps, handpressure, or other pressure application. Method 600 may includeoperation 607 of securing the slab to the mold by applying one or moreweights or clamps such as hand clamps, bar clamps, parallel clamps,pneumatic clamps, hydraulic clamps, or the like.

Forming the slab to the mold can include an iterative process ofsuccessively bending the slab toward the shape of the mold as the slabwarms. One or more clamping mechanisms may be added or adjusted instages (e.g., every minute, every 15 minutes, etc.) to gradually causethe slab to conform to the shape of the mold. For example, operation 607may include clamping the slab in a curved configuration having a minimumradius of curvature greater than that of the corresponding curvedsurface of the mold for a first period of time while heat issimultaneously applied to first and second major surfaces of the slab,and clamping the slab in a curved configuration having a minimum radiusof curvature substantially equal to that of the corresponding curvedsurface of the mold for a second period of time while heat issimultaneously applied to the first and second major surfaces. In thisway, the slab can be gradually adjusted to conform to the mold.

Exemplary method 600 further includes operation 608 of allowing the slabto cool. Step 608 may, in some embodiments, commence directly after aslab has conformed to a mold, while in other embodiments, step 608 cancommence a period of time after the slab has conformed to a mold. Forexample, after a slab has been secured to the mold in a desired shape,operation 605 of applying heat to the slab may cease such that the slabmay cool. In some exemplary embodiments, a slab is allowed to cool for aperiod of time sufficient for the temperature of the slab to drop belowthe moldable temperature. In some embodiments, the slab is cooled to atemperature lower than 35° C. below the Tg of one or more components ofthe slab, a temperature lower than 45° C. below the Tg of one or morecomponents of the slab, a temperature lower than 55° C. below the Tg ofone or more components of the slab, a temperature lower than 65° C.below the Tg of one or more components of the slab. In some embodiments,the slab is cooled to a temperature lower than 35° C. below the alteredTg of one or more components of the slab, a temperature lower than 45°C. below the altered Tg of one or more components of the slab, atemperature lower than 55° C. below the altered Tg of one or morecomponents of the slab, a temperature lower than 65° C. below thealtered Tg of one or more components of the slab. In some embodiments,the slab is cooled to a temperature lower than 35° C. below the minimummoldable temperature of one or more components of the slab, atemperature lower than 45° C. below the minimum moldable temperature ofone or more components of the slab, a temperature lower than 55° C.below the minimum moldable temperature of one or more components of theslab, a temperature lower than 65° C. below the minimum moldabletemperature of one or more components of the slab.

Operation 608 may include passively cooling the slab, such as byremoving application of heat. Alternatively or additionally, operation608 may include actively cooling the slab, e.g. by blowing cool airacross the slab, delivering a cool water bath to the slab, etc.

Method 600 further includes operation 609 of removing the slab from themold. The slab removed from the mold may have a curved shape similar toa curved shape of the mold (e.g., as shown in FIGS. 1-5). In someembodiments, the slab may remain on the mold while operations 605, 606,607, and/or 608 may be repeated to form another portion of the slab.After operation 609, the slab may proceed to one or more finishingoperations, such as cutting, polishing or other treatment. For example,the slab may proceed to one or more finishing operations during which amajor surface of the slab is finished, such as by polishing to a smoothfinish, or otherwise imparting a polished, matte, honed, raw, or otherfinish.

In an exemplary embodiment, one or more operations 600 can be repeatedone or more times on the same slab to form multiple different curvesacross the dimensions of the slab. In some embodiments, method 600 canbe repeated one or more times on the same slab to form a single curve inmultiple steps. In some exemplary embodiments, one or more operationsmay be repeated at a similar location of the slab to generate complex ororganic curved surfaces that curve in multiple directions (e.g., aboutmultiple different axes).

The operations of exemplary method 600 may follow any suitable sequence,and/or may be performed in parallel. For example, operation 605 ofapplying heat may be conducted during at least portions of operation 606of forming the slab to the mold and operation 607 while the slab issecured to the mold. Likewise, operation 608 of cooling the slab may beconducted during at least portions of operation 606 of forming the slabto the mold and operation 607 while the slab is secured to the mold. Insome exemplary embodiments, one or more surfaces of the stone slab maybe treated or finished before a curve is imparted by method 600. Forexample, the slab may proceed to one or more finishing operations duringwhich a surface of the slab is finished, such as by polishing to asmooth finish, or otherwise imparting a polished, matte, honed, raw, orother finish. The slab may be curved via one or more operations ofmethod 600 without substantially affecting the surface (e.g. such thatthe polished, matte, honed, raw, or other finish is maintained and/or asubsequent finishing operation is not required to impart the polished,matte, honed, raw, or other finish). Alternatively or additionally, oneor more steps depicted in FIG. 6 may be omitted, and one or moreintermediate steps may be added.

Multiple curves and configurations of curves can be created in slabsaccording to the methods described herein. In some embodiments, asecond, third, fourth, or additional curve can be on a portion of a slabthat is not part of a first curve. In some embodiments, a second, third,fourth, or later curve can be made on a portion of a first or othercurve. In some embodiments, slabs having varying radii of curvature areformed, such as organic shapes where the slabs bend at more than oneangle and/or with varying degrees of curvature. In some embodiments,multiple molds may be used to form a single curve having multipledifferent curved shapes. In some embodiments, consecutive curves canbend in the same direction. In some embodiments, consecutive curves canbend in different directions. Exemplary configurations can include, butare not limited to, final slabs having a c-like shape, slabs having ans-like shape, slabs with symmetric or asymmetric curves, slabs having acurved step-like configuration, slabs with two or more curves having thesame radius of curvature, slabs having two or more curves each having adifferent radius of curvature, etc.

The curved slabs described herein can be further processed, for example,cut, milled, machined, or otherwise processed to various shapes andsizes (e.g., to provide custom-fit countertop surfaces with optionalholes for sinks, faucets, or other amenities, building materials thatconform to a particular structure, etc.).

While this specification contains many specific implementation details,these should not be construed as limitations on the scope of anyinvention or of what may be claimed, but rather as descriptions offeatures that may be specific to particular embodiments. Certainfeatures that are described in this specification in the context ofseparate embodiments can also be implemented in combination in a singleembodiment in part or in whole. Conversely, various features that aredescribed in the context of a single embodiment can also be implementedin multiple embodiments separately or in any subcombination. Moreover,although features may be described herein as acting in certaincombinations and/or initially claimed as such, one or more features froma claimed combination can in some cases be exercised separate from thecombination, and the claimed combination may be directed to asubcombination or variation of a subcombination.

Similarly, while operations are depicted in the drawings in a particularorder, this should not be understood as requiring that such operationsbe performed in the particular order shown or in sequential order, orthat all illustrated operations be performed, to achieve desirableresults. Although a number of implementations have been described indetail above, other modifications are possible. For example, the logicflows depicted in the figures do not require the particular order shown,or sequential order, to achieve desirable results. In addition, othersteps may be provided, or steps may be eliminated, from the describedflows, and other components may be added to, or removed from, thedescribed systems. Accordingly, other aspects, advantages,modifications, and implementations are within the scope of the followingclaims.

1.-61. (canceled)
 62. A method of thermoforming a slab, comprising: applying non-conductive heat simultaneously to a first major surface and a second major surface of a slab comprising particulate material and a resin binder, the first major surface separated from the second major surface by a slab thickness; and forming the slab to a mold while applying the heat to the first and second major surfaces.
 63. The method of claim 62, wherein the mold comprises a curved molding surface, and forming the slab to the mold comprises applying the non-conductive heat to the first and second major surfaces of the slab while at least one of the major surfaces is urged toward the curved molding surface of the mold.
 64. The method of claim 62, wherein applying non-conductive heat comprises providing radiant heat to the first major surface of the slab.
 65. The method of claim 64, wherein applying non-conductive heat comprises providing radiant heat to the second major surface of the slab.
 66. The method of claim 62, wherein applying non-conductive heat comprises providing convective heat to the first major surface of the slab.
 67. The method of claim 66, wherein applying non-conductive heat comprises providing convective heat to the second major surface of the slab.
 68. The method of claim 62, wherein forming the slab comprises forming a curve having a radius of curvature of less than 100 inches.
 69. The method of claim 68, wherein forming the slab comprises forming a curve having a radius of curvature between 23 inches and 70 inches.
 70. The method of claim 69, wherein the radius of curvature is a minimum radius of curvature.
 71. The method of claim 62, wherein the slab comprises a pigment.
 72. The method of claim 71, wherein the particulate material comprises predominantly quartz.
 73. The method of claim 62, wherein the slab has a first major surface and a second major surface separated by a thickness, and the thickness is between 0.001 inches and 3 inches.
 74. The method of claim 72, comprising manufacturing the slab by compacting, compressing, and at least partially curing the slab prior to applying the non-conductive heat to the slab.
 75. The method of claim 74, wherein applying non-conductive heat comprises applying heat above a slab moldable temperature, the slab at least partially malleable when heated to the slab moldable temperature.
 76. The method of claim 74, wherein the slab comprises a binder material having a glass transition temperature (Tg), and wherein applying non-conductive heat comprises applying heat at a temperature within 20° C. of the glass transition temperature (Tg) according to dynamic mechanical analysis.
 77. The method of claim 62, comprising: clamping the slab in a first curved configuration for a first period of time while heat is applied to the first and second major surfaces to form a first curve having a first radius of curvature; and clamping the slab in a second curved configuration for a second period of time while heat is applied to the first and second major surfaces to form a second curve having a second radius of curvature.
 78. A method of thermoforming a slab, comprising: applying radiant heat simultaneously to a first major surface and a second major surface of a slab, the first major surface separated from the second major surface by a slab thickness; and forming the slab to a mold while applying the radiant heat to the first and second major surfaces, the mold comprising a curved molding surface, at least one of the major surfaces of the slab urged toward the curved molding surface of the mold while applying the radiant heat to the first and second major surfaces of the slab; wherein the resulting slab includes a curve having a minimum radius of curvature between 18 inches and 100 inches.
 79. The method of claim 78, wherein applying non-conductive heat comprises providing radiant heat to the first and second major surfaces of the slab.
 80. The method of claim 78, comprising manufacturing the slab by compacting, compressing, and at least partially curing the slab prior to applying the non-conductive heat to the slab.
 81. The method of claim 80, wherein applying non-conductive heat comprises applying heat above a slab moldable temperature, the slab at least partially malleable when heated to the slab moldable temperature. 